<?php

/**
 * Smarty Internal Plugin Smarty Template Compiler Base
 * This file contains the basic classes and methods for compiling Smarty templates with lexer/parser
 *
 * @package    Smarty
 * @subpackage Compiler
 * @author     Uwe Tews
 */

/**
 * Main abstract compiler class
 *
 * @package    Smarty
 * @subpackage Compiler
 *
 * @property Smarty_Internal_SmartyTemplateCompiler $prefixCompiledCode  = ''
 * @property Smarty_Internal_SmartyTemplateCompiler $postfixCompiledCode = ''
 * @method registerPostCompileCallback($callback, $parameter = array(), $key = null, $replace = false)
 * @method unregisterPostCompileCallback($key)
 */
abstract class Smarty_Internal_TemplateCompilerBase {

	/**
	 * Smarty object
	 *
	 * @var Smarty
	 */
	public $smarty = null;

	/**
	 * Parser object
	 *
	 * @var Smarty_Internal_Templateparser
	 */
	public $parser = null;

	/**
	 * hash for nocache sections
	 *
	 * @var mixed
	 */
	public $nocache_hash = null;

	/**
	 * suppress generation of nocache code
	 *
	 * @var bool
	 */
	public $suppressNocacheProcessing = false;

	/**
	 * compile tag objects cache
	 *
	 * @var array
	 */
	static $_tag_objects = array();

	/**
	 * tag stack
	 *
	 * @var array
	 */
	public $_tag_stack = array();

	/**
	 * current template
	 *
	 * @var Smarty_Internal_Template
	 */
	public $template = null;

	/**
	 * merged included sub template data
	 *
	 * @var array
	 */
	public $mergedSubTemplatesData = array();

	/**
	 * merged sub template code
	 *
	 * @var array
	 */
	public $mergedSubTemplatesCode = array();

	/**
	 * collected template properties during compilation
	 *
	 * @var array
	 */
	public $templateProperties = array();

	/**
	 * source line offset for error messages
	 *
	 * @var int
	 */
	public $trace_line_offset = 0;

	/**
	 * trace uid
	 *
	 * @var string
	 */
	public $trace_uid = '';

	/**
	 * trace file path
	 *
	 * @var string
	 */
	public $trace_filepath = '';

	/**
	 * stack for tracing file and line of nested {block} tags
	 *
	 * @var array
	 */
	public $trace_stack = array();

	/**
	 * plugins loaded by default plugin handler
	 *
	 * @var array
	 */
	public $default_handler_plugins = array();

	/**
	 * saved preprocessed modifier list
	 *
	 * @var mixed
	 */
	public $default_modifier_list = null;

	/**
	 * force compilation of complete template as nocache
	 *
	 * @var boolean
	 */
	public $forceNocache = false;

	/**
	 * flag if compiled template file shall we written
	 *
	 * @var bool
	 */
	public $write_compiled_code = true;

	/**
	 * Template functions
	 *
	 * @var array
	 */
	public $tpl_function = array();

	/**
	 * called sub functions from template function
	 *
	 * @var array
	 */
	public $called_functions = array();

	/**
	 * compiled template or block function code
	 *
	 * @var string
	 */
	public $blockOrFunctionCode = '';

	/**
	 * php_handling setting either from Smarty or security
	 *
	 * @var int
	 */
	public $php_handling = 0;

	/**
	 * flags for used modifier plugins
	 *
	 * @var array
	 */
	public $modifier_plugins = array();

	/**
	 * type of already compiled modifier
	 *
	 * @var array
	 */
	public $known_modifier_type = array();

	/**
	 * parent compiler object for merged subtemplates and template functions
	 *
	 * @var Smarty_Internal_TemplateCompilerBase
	 */
	public $parent_compiler = null;

	/**
	 * Flag true when compiling nocache section
	 *
	 * @var bool
	 */
	public $nocache = false;

	/**
	 * Flag true when tag is compiled as nocache
	 *
	 * @var bool
	 */
	public $tag_nocache = false;

	/**
	 * Compiled tag prefix code
	 *
	 * @var array
	 */
	public $prefix_code = array();

	/**
	 * Prefix code  stack
	 *
	 * @var array
	 */
	public $prefixCodeStack = array();

	/**
	 * Tag has compiled code
	 *
	 * @var bool
	 */
	public $has_code = false;

	/**
	 * A variable string was compiled
	 *
	 * @var bool
	 */
	public $has_variable_string = false;

	/**
	 * Tag creates output
	 *
	 * @var bool
	 */
	public $has_output = false;

	/**
	 * Stack for {setfilter} {/setfilter}
	 *
	 * @var array
	 */
	public $variable_filter_stack = array();

	/**
	 * variable filters for {setfilter} {/setfilter}
	 *
	 * @var array
	 */
	public $variable_filters = array();

	/**
	 * Nesting count of looping tags like {foreach}, {for}, {section}, {while}
	 *
	 * @var int
	 */
	public $loopNesting = 0;

	/**
	 * Strip preg pattern
	 *
	 * @var string
	 */
	public $stripRegEx = '![\t ]*[\r\n]+[\t ]*!';

	/**
	 * plugin search order
	 *
	 * @var array
	 */
	public $plugin_search_order = array('function', 'block', 'compiler', 'class');

	/**
	 * General storage area for tag compiler plugins
	 *
	 * @var array
	 */
	public $_cache = array();

	/**
	 * counter for prefix variable number
	 *
	 * @var int
	 */
	public static $prefixVariableNumber = 0;

	/**
	 * method to compile a Smarty template
	 *
	 * @param mixed $_content template source
	 * @param bool  $isTemplateSource
	 *
	 * @return bool true if compiling succeeded, false if it failed
	 */
	abstract protected function doCompile($_content, $isTemplateSource = false);

	/**
	 * Initialize compiler
	 *
	 * @param Smarty $smarty global instance
	 */
	public function __construct(Smarty $smarty) {
		$this->smarty = $smarty;
		$this->nocache_hash = str_replace(array('.', ','), '_', uniqid(rand(), true));
	}

	/**
	 * Method to compile a Smarty template
	 *
	 * @param  Smarty_Internal_Template                 $template template object to compile
	 * @param  bool                                     $nocache  true is shall be compiled in nocache mode
	 * @param null|Smarty_Internal_TemplateCompilerBase $parent_compiler
	 *
	 * @return bool true if compiling succeeded, false if it failed
	 * @throws \Exception
	 */
	public function compileTemplate(Smarty_Internal_Template $template, $nocache = null,
		Smarty_Internal_TemplateCompilerBase $parent_compiler = null) {
		// get code frame of compiled template
		$_compiled_code = $template->smarty->ext->_codeFrame->create($template,
			$this->compileTemplateSource($template, $nocache,
				$parent_compiler),
			$this->postFilter($this->blockOrFunctionCode) .
			join('', $this->mergedSubTemplatesCode), false,
			$this);
		return $_compiled_code;
	}

	/**
	 * Compile template source and run optional post filter
	 *
	 * @param \Smarty_Internal_Template             $template
	 * @param null|bool                             $nocache flag if template must be compiled in nocache mode
	 * @param \Smarty_Internal_TemplateCompilerBase $parent_compiler
	 *
	 * @return string
	 * @throws \Exception
	 */
	public function compileTemplateSource(Smarty_Internal_Template $template, $nocache = null,
		Smarty_Internal_TemplateCompilerBase $parent_compiler = null) {
		try {
			// save template object in compiler class
			$this->template = $template;
			if (property_exists($this->template->smarty, 'plugin_search_order')) {
				$this->plugin_search_order = $this->template->smarty->plugin_search_order;
			}
			if ($this->smarty->debugging) {
				if (!isset($this->smarty->_debug)) {
					$this->smarty->_debug = new Smarty_Internal_Debug();
				}
				$this->smarty->_debug->start_compile($this->template);
			}
			if (isset($this->template->smarty->security_policy)) {
				$this->php_handling = $this->template->smarty->security_policy->php_handling;
			} else {
				$this->php_handling = $this->template->smarty->php_handling;
			}
			$this->parent_compiler = $parent_compiler ? $parent_compiler : $this;
			$nocache = isset($nocache) ? $nocache : false;
			if (empty($template->compiled->nocache_hash)) {
				$template->compiled->nocache_hash = $this->nocache_hash;
			} else {
				$this->nocache_hash = $template->compiled->nocache_hash;
			}
			// flag for nocache sections
			$this->nocache = $nocache;
			$this->tag_nocache = false;
			// reset has nocache code flag
			$this->template->compiled->has_nocache_code = false;
			$this->has_variable_string = false;
			$this->prefix_code = array();
			// add file dependency
			if ($this->smarty->merge_compiled_includes || $this->template->source->handler->checkTimestamps()) {
				$this->parent_compiler->template->compiled->file_dependency[$this->template->source->uid] =
				array($this->template->source->filepath, $this->template->source->getTimeStamp(),
					$this->template->source->type);
			}
			$this->smarty->_current_file = $this->template->source->filepath;
			// get template source
			if (!empty($this->template->source->components)) {
				// we have array of inheritance templates by extends: resource
				// generate corresponding source code sequence
				$_content =
				Smarty_Internal_Compile_Extends::extendsSourceArrayCode($this->template->source->components);
			} else {
				// get template source
				$_content = $this->template->source->getContent();
			}
			$_compiled_code = $this->postFilter($this->doCompile($this->preFilter($_content), true));
		} catch (Exception $e) {
			if ($this->smarty->debugging) {
				$this->smarty->_debug->end_compile($this->template);
			}
			$this->_tag_stack = array();
			// free memory
			$this->parent_compiler = null;
			$this->template = null;
			$this->parser = null;
			throw $e;
		}
		if ($this->smarty->debugging) {
			$this->smarty->_debug->end_compile($this->template);
		}
		$this->parent_compiler = null;
		$this->parser = null;
		return $_compiled_code;
	}

	/**
	 * Optionally process compiled code by post filter
	 *
	 * @param string $code compiled code
	 *
	 * @return string
	 * @throws \SmartyException
	 */
	public function postFilter($code) {
		// run post filter if on code
		if (!empty($code) &&
			(isset($this->smarty->autoload_filters['post']) || isset($this->smarty->registered_filters['post']))
		) {
			return $this->smarty->ext->_filterHandler->runFilter('post', $code, $this->template);
		} else {
			return $code;
		}
	}

	/**
	 * Run optional prefilter
	 *
	 * @param string $_content template source
	 *
	 * @return string
	 * @throws \SmartyException
	 */
	public function preFilter($_content) {
		// run pre filter if required
		if ($_content != '' &&
			((isset($this->smarty->autoload_filters['pre']) || isset($this->smarty->registered_filters['pre'])))
		) {
			return $this->smarty->ext->_filterHandler->runFilter('pre', $_content, $this->template);
		} else {
			return $_content;
		}
	}

	/**
	 * Compile Tag
	 * This is a call back from the lexer/parser
	 *
	 * Save current prefix code
	 * Compile tag
	 * Merge tag prefix code with saved one
	 * (required nested tags in attributes)
	 *
	 * @param  string $tag       tag name
	 * @param  array  $args      array with tag attributes
	 * @param  array  $parameter array with compilation parameter
	 *
	 * @throws SmartyCompilerException
	 * @throws SmartyException
	 * @return string compiled code
	 */
	public function compileTag($tag, $args, $parameter = array()) {
		$this->prefixCodeStack[] = $this->prefix_code;
		$this->prefix_code = array();
		$result = $this->compileTag2($tag, $args, $parameter);
		$this->prefix_code = array_merge($this->prefix_code, array_pop($this->prefixCodeStack));
		return $result;
	}

	/**
	 * Compile Tag
	 *
	 * @param  string $tag       tag name
	 * @param  array  $args      array with tag attributes
	 * @param  array  $parameter array with compilation parameter
	 *
	 * @throws SmartyCompilerException
	 * @throws SmartyException
	 * @return string compiled code
	 */
	private function compileTag2($tag, $args, $parameter) {
		$plugin_type = '';
		// $args contains the attributes parsed and compiled by the lexer/parser
		// assume that tag does compile into code, but creates no HTML output
		$this->has_code = true;
		$this->has_output = false;
		// log tag/attributes
		if (isset($this->smarty->_cache['get_used_tags'])) {
			$this->template->_cache['used_tags'][] = array($tag, $args);
		}
		// check nocache option flag
		foreach ($args as $arg) {
			if (!is_array($arg)) {
				if ($arg == "'nocache'") {
					$this->tag_nocache = true;
				}
			} else {
				foreach ($arg as $k => $v) {
					if ($k == "'nocache'" && (trim($v, "'\" ") == 'true')) {
						$this->tag_nocache = true;
					}
				}
			}
		}
		// compile the smarty tag (required compile classes to compile the tag are auto loaded)
		if (($_output = $this->callTagCompiler($tag, $args, $parameter)) === false) {
			if (isset($this->parent_compiler->tpl_function[$tag])) {
				// template defined by {template} tag
				$args['_attr']['name'] = "'" . $tag . "'";
				$_output = $this->callTagCompiler('call', $args, $parameter);
			}
		}
		if ($_output !== false) {
			if ($_output !== true) {
				// did we get compiled code
				if ($this->has_code) {
					// Does it create output?
					if ($this->has_output) {
						$_output .= "\n";
					}
					// return compiled code
					return $_output;
				}
			}
			// tag did not produce compiled code
			return null;
		} else {
			// map_named attributes
			if (isset($args['_attr'])) {
				foreach ($args['_attr'] as $key => $attribute) {
					if (is_array($attribute)) {
						$args = array_merge($args, $attribute);
					}
				}
			}
			// not an internal compiler tag
			if (strlen($tag) < 6 || substr($tag, -5) != 'close') {
				// check if tag is a registered object
				if (isset($this->smarty->registered_objects[$tag]) && isset($parameter['object_method'])) {
					$method = $parameter['object_method'];
					if (!in_array($method, $this->smarty->registered_objects[$tag][3]) &&
						(empty($this->smarty->registered_objects[$tag][1]) ||
							in_array($method, $this->smarty->registered_objects[$tag][1]))
					) {
						return $this->callTagCompiler('private_object_function', $args, $parameter, $tag, $method);
					} elseif (in_array($method, $this->smarty->registered_objects[$tag][3])) {
						return $this->callTagCompiler('private_object_block_function', $args, $parameter, $tag,
							$method);
					} else {
						// throw exception
						$this->trigger_template_error('not allowed method "' . $method . '" in registered object "' .
							$tag . '"', null, true);
					}
				}
				// check if tag is registered
				foreach (array(Smarty::PLUGIN_COMPILER, Smarty::PLUGIN_FUNCTION, Smarty::PLUGIN_BLOCK) as $plugin_type) {
					if (isset($this->smarty->registered_plugins[$plugin_type][$tag])) {
						// if compiler function plugin call it now
						if ($plugin_type == Smarty::PLUGIN_COMPILER) {
							$new_args = array();
							foreach ($args as $key => $mixed) {
								if (is_array($mixed)) {
									$new_args = array_merge($new_args, $mixed);
								} else {
									$new_args[$key] = $mixed;
								}
							}
							if (!$this->smarty->registered_plugins[$plugin_type][$tag][1]) {
								$this->tag_nocache = true;
							}
							return call_user_func_array($this->smarty->registered_plugins[$plugin_type][$tag][0],
								array($new_args, $this));
						}
						// compile registered function or block function
						if ($plugin_type == Smarty::PLUGIN_FUNCTION || $plugin_type == Smarty::PLUGIN_BLOCK) {
							return $this->callTagCompiler('private_registered_' . $plugin_type, $args, $parameter,
								$tag);
						}
					}
				}
				// check plugins from plugins folder
				foreach ($this->plugin_search_order as $plugin_type) {
					if ($plugin_type == Smarty::PLUGIN_COMPILER &&
						$this->smarty->loadPlugin('smarty_compiler_' . $tag) &&
						(!isset($this->smarty->security_policy) ||
							$this->smarty->security_policy->isTrustedTag($tag, $this))
					) {
						$plugin = 'smarty_compiler_' . $tag;
						if (is_callable($plugin)) {
							// convert arguments format for old compiler plugins
							$new_args = array();
							foreach ($args as $key => $mixed) {
								if (is_array($mixed)) {
									$new_args = array_merge($new_args, $mixed);
								} else {
									$new_args[$key] = $mixed;
								}
							}

							return $plugin($new_args, $this->smarty);
						}
						if (class_exists($plugin, false)) {
							$plugin_object = new $plugin;
							if (method_exists($plugin_object, 'compile')) {
								return $plugin_object->compile($args, $this);
							}
						}
						throw new SmartyException("Plugin \"{$tag}\" not callable");
					} else {
						if ($function = $this->getPlugin($tag, $plugin_type)) {
							if (!isset($this->smarty->security_policy) ||
								$this->smarty->security_policy->isTrustedTag($tag, $this)
							) {
								return $this->callTagCompiler('private_' . $plugin_type . '_plugin', $args, $parameter,
									$tag, $function);
							}
						}
					}
				}
				if (is_callable($this->smarty->default_plugin_handler_func)) {
					$found = false;
					// look for already resolved tags
					foreach ($this->plugin_search_order as $plugin_type) {
						if (isset($this->default_handler_plugins[$plugin_type][$tag])) {
							$found = true;
							break;
						}
					}
					if (!$found) {
						// call default handler
						foreach ($this->plugin_search_order as $plugin_type) {
							if ($this->getPluginFromDefaultHandler($tag, $plugin_type)) {
								$found = true;
								break;
							}
						}
					}
					if ($found) {
						// if compiler function plugin call it now
						if ($plugin_type == Smarty::PLUGIN_COMPILER) {
							$new_args = array();
							foreach ($args as $mixed) {
								$new_args = array_merge($new_args, $mixed);
							}
							return call_user_func_array($this->default_handler_plugins[$plugin_type][$tag][0],
								array($new_args, $this));
						} else {
							return $this->callTagCompiler('private_registered_' . $plugin_type, $args, $parameter,
								$tag);
						}
					}
				}
			} else {
				// compile closing tag of block function
				$base_tag = substr($tag, 0, -5);
				// check if closing tag is a registered object
				if (isset($this->smarty->registered_objects[$base_tag]) && isset($parameter['object_method'])) {
					$method = $parameter['object_method'];
					if (in_array($method, $this->smarty->registered_objects[$base_tag][3])) {
						return $this->callTagCompiler('private_object_block_function', $args, $parameter, $tag,
							$method);
					} else {
						// throw exception
						$this->trigger_template_error('not allowed closing tag method "' . $method .
							'" in registered object "' . $base_tag . '"', null, true);
					}
				}
				// registered block tag ?
				if (isset($this->smarty->registered_plugins[Smarty::PLUGIN_BLOCK][$base_tag]) ||
					isset($this->default_handler_plugins[Smarty::PLUGIN_BLOCK][$base_tag])
				) {
					return $this->callTagCompiler('private_registered_block', $args, $parameter, $tag);
				}
				// registered function tag ?
				if (isset($this->smarty->registered_plugins[Smarty::PLUGIN_FUNCTION][$tag])) {
					return $this->callTagCompiler('private_registered_function', $args, $parameter, $tag);
				}
				// block plugin?
				if ($function = $this->getPlugin($base_tag, Smarty::PLUGIN_BLOCK)) {
					return $this->callTagCompiler('private_block_plugin', $args, $parameter, $tag, $function);
				}
				// function plugin?
				if ($function = $this->getPlugin($tag, Smarty::PLUGIN_FUNCTION)) {
					if (!isset($this->smarty->security_policy) ||
						$this->smarty->security_policy->isTrustedTag($tag, $this)
					) {
						return $this->callTagCompiler('private_function_plugin', $args, $parameter, $tag, $function);
					}
				}
				// registered compiler plugin ?
				if (isset($this->smarty->registered_plugins[Smarty::PLUGIN_COMPILER][$tag])) {
					// if compiler function plugin call it now
					$args = array();
					if (!$this->smarty->registered_plugins[Smarty::PLUGIN_COMPILER][$tag][1]) {
						$this->tag_nocache = true;
					}
					return call_user_func_array($this->smarty->registered_plugins[Smarty::PLUGIN_COMPILER][$tag][0],
						array($args, $this));
				}
				if ($this->smarty->loadPlugin('smarty_compiler_' . $tag)) {
					$plugin = 'smarty_compiler_' . $tag;
					if (is_callable($plugin)) {
						return $plugin($args, $this->smarty);
					}
					if (class_exists($plugin, false)) {
						$plugin_object = new $plugin;
						if (method_exists($plugin_object, 'compile')) {
							return $plugin_object->compile($args, $this);
						}
					}
					throw new SmartyException("Plugin \"{$tag}\" not callable");
				}
			}
			$this->trigger_template_error("unknown tag \"" . $tag . "\"", null, true);
		}
	}

	/**
	 * compile variable
	 *
	 * @param string $variable
	 *
	 * @return string
	 */
	public function compileVariable($variable) {
		if (strpos($variable, '(') == 0) {
			// not a variable variable
			$var = trim($variable, '\'');
			$this->tag_nocache = $this->tag_nocache |
			$this->template->ext->getTemplateVars->_getVariable($this->template, $var, null, true,
				false)->nocache;
			// todo $this->template->compiled->properties['variables'][$var] = $this->tag_nocache | $this->nocache;
		}
		return '$_smarty_tpl->tpl_vars[' . $variable . ']->value';
	}

	/**
	 * compile config variable
	 *
	 * @param string $variable
	 *
	 * @return string
	 */
	public function compileConfigVariable($variable) {
		// return '$_smarty_tpl->config_vars[' . $variable . ']';
		return '$_smarty_tpl->smarty->ext->configLoad->_getConfigVariable($_smarty_tpl, ' . $variable . ')';
	}

	/**
	 * This method is called from parser to process a text content section
	 * - remove text from inheritance child templates as they may generate output
	 * - strip text if strip is enabled
	 *
	 * @param string $text
	 *
	 * @return null|\Smarty_Internal_ParseTree_Text
	 */
	public function processText($text) {
		if ((string) $text != '') {
			$store = array();
			$_store = 0;
			if ($this->parser->strip) {
				if (strpos($text, '<') !== false) {
					// capture html elements not to be messed with
					$_offset = 0;
					if (preg_match_all('#(<script[^>]*>.*?</script[^>]*>)|(<textarea[^>]*>.*?</textarea[^>]*>)|(<pre[^>]*>.*?</pre[^>]*>)#is',
						$text, $matches, PREG_OFFSET_CAPTURE | PREG_SET_ORDER)) {
						foreach ($matches as $match) {
							$store[] = $match[0][0];
							$_length = strlen($match[0][0]);
							$replace = '@!@SMARTY:' . $_store . ':SMARTY@!@';
							$text = substr_replace($text, $replace, $match[0][1] - $_offset, $_length);

							$_offset += $_length - strlen($replace);
							$_store++;
						}
					}
					$expressions = array( // replace multiple spaces between tags by a single space
						'#(:SMARTY@!@|>)[\040\011]+(?=@!@SMARTY:|<)#s' => '\1 \2',
						// remove newline between tags
						'#(:SMARTY@!@|>)[\040\011]*[\n]\s*(?=@!@SMARTY:|<)#s' => '\1\2',
						// remove multiple spaces between attributes (but not in attribute values!)
						'#(([a-z0-9]\s*=\s*("[^"]*?")|(\'[^\']*?\'))|<[a-z0-9_]+)\s+([a-z/>])#is' => '\1 \5',
						'#>[\040\011]+$#Ss' => '> ', '#>[\040\011]*[\n]\s*$#Ss' => '>',
						$this->stripRegEx => '');

					$text = preg_replace(array_keys($expressions), array_values($expressions), $text);
					$_offset = 0;
					if (preg_match_all('#@!@SMARTY:([0-9]+):SMARTY@!@#is', $text, $matches,
						PREG_OFFSET_CAPTURE | PREG_SET_ORDER)) {
						foreach ($matches as $match) {
							$_length = strlen($match[0][0]);
							$replace = $store[$match[1][0]];
							$text = substr_replace($text, $replace, $match[0][1] + $_offset, $_length);

							$_offset += strlen($replace) - $_length;
							$_store++;
						}
					}
				} else {
					$text = preg_replace($this->stripRegEx, '', $text);
				}
			}
			return new Smarty_Internal_ParseTree_Text($text);
		}
		return null;
	}

	/**
	 * lazy loads internal compile plugin for tag and calls the compile method
	 * compile objects cached for reuse.
	 * class name format:  Smarty_Internal_Compile_TagName
	 * plugin filename format: Smarty_Internal_TagName.php
	 *
	 * @param  string $tag    tag name
	 * @param  array  $args   list of tag attributes
	 * @param  mixed  $param1 optional parameter
	 * @param  mixed  $param2 optional parameter
	 * @param  mixed  $param3 optional parameter
	 *
	 * @return string compiled code
	 */
	public function callTagCompiler($tag, $args, $param1 = null, $param2 = null, $param3 = null) {
		// re-use object if already exists
		if (!isset(self::$_tag_objects[$tag])) {
			// lazy load internal compiler plugin
			$_tag = explode('_', $tag);
			$_tag = array_map('ucfirst', $_tag);
			$class_name = 'Smarty_Internal_Compile_' . implode('_', $_tag);
			if (class_exists($class_name) &&
				(!isset($this->smarty->security_policy) || $this->smarty->security_policy->isTrustedTag($tag, $this))
			) {
				self::$_tag_objects[$tag] = new $class_name;
			} else {
				self::$_tag_objects[$tag] = false;
				return false;
			}
		}
		// compile this tag
		return self::$_tag_objects[$tag] === false ? false :
		self::$_tag_objects[$tag]->compile($args, $this, $param1, $param2, $param3);
	}

	/**
	 * Check for plugins and return function name
	 *
	 * @param         $plugin_name
	 * @param  string $plugin_type type of plugin
	 *
	 * @return string call name of function
	 */
	public function getPlugin($plugin_name, $plugin_type) {
		$function = null;
		if ($this->template->caching && ($this->nocache || $this->tag_nocache)) {
			if (isset($this->parent_compiler->template->compiled->required_plugins['nocache'][$plugin_name][$plugin_type])) {
				$function =
				$this->parent_compiler->template->compiled->required_plugins['nocache'][$plugin_name][$plugin_type]['function'];
			} elseif (isset($this->parent_compiler->template->compiled->required_plugins['compiled'][$plugin_name][$plugin_type])) {
				$this->parent_compiler->template->compiled->required_plugins['nocache'][$plugin_name][$plugin_type] =
				$this->parent_compiler->template->compiled->required_plugins['compiled'][$plugin_name][$plugin_type];
				$function =
				$this->parent_compiler->template->compiled->required_plugins['nocache'][$plugin_name][$plugin_type]['function'];
			}
		} else {
			if (isset($this->parent_compiler->template->compiled->required_plugins['compiled'][$plugin_name][$plugin_type])) {
				$function =
				$this->parent_compiler->template->compiled->required_plugins['compiled'][$plugin_name][$plugin_type]['function'];
			} elseif (isset($this->parent_compiler->template->compiled->required_plugins['nocache'][$plugin_name][$plugin_type])) {
				$this->parent_compiler->template->compiled->required_plugins['compiled'][$plugin_name][$plugin_type] =
				$this->parent_compiler->template->compiled->required_plugins['nocache'][$plugin_name][$plugin_type];
				$function =
				$this->parent_compiler->template->compiled->required_plugins['compiled'][$plugin_name][$plugin_type]['function'];
			}
		}
		if (isset($function)) {
			if ($plugin_type == 'modifier') {
				$this->modifier_plugins[$plugin_name] = true;
			}

			return $function;
		}
		// loop through plugin dirs and find the plugin
		$function = 'smarty_' . $plugin_type . '_' . $plugin_name;
		$file = $this->smarty->loadPlugin($function, false);

		if (is_string($file)) {
			if ($this->template->caching && ($this->nocache || $this->tag_nocache)) {
				$this->parent_compiler->template->compiled->required_plugins['nocache'][$plugin_name][$plugin_type]['file'] =
					$file;
				$this->parent_compiler->template->compiled->required_plugins['nocache'][$plugin_name][$plugin_type]['function'] =
					$function;
			} else {
				$this->parent_compiler->template->compiled->required_plugins['compiled'][$plugin_name][$plugin_type]['file'] =
					$file;
				$this->parent_compiler->template->compiled->required_plugins['compiled'][$plugin_name][$plugin_type]['function'] =
					$function;
			}
			if ($plugin_type == 'modifier') {
				$this->modifier_plugins[$plugin_name] = true;
			}

			return $function;
		}
		if (is_callable($function)) {
			// plugin function is defined in the script
			return $function;
		}

		return false;
	}

	/**
	 * Check for plugins by default plugin handler
	 *
	 * @param  string $tag         name of tag
	 * @param  string $plugin_type type of plugin
	 *
	 * @return boolean true if found
	 */
	public function getPluginFromDefaultHandler($tag, $plugin_type) {
		$callback = null;
		$script = null;
		$cacheable = true;
		$result = call_user_func_array($this->smarty->default_plugin_handler_func,
			array($tag, $plugin_type, $this->template, &$callback, &$script, &$cacheable));
		if ($result) {
			$this->tag_nocache = $this->tag_nocache || !$cacheable;
			if ($script !== null) {
				if (is_file($script)) {
					if ($this->template->caching && ($this->nocache || $this->tag_nocache)) {
						$this->parent_compiler->template->compiled->required_plugins['nocache'][$tag][$plugin_type]['file'] =
							$script;
						$this->parent_compiler->template->compiled->required_plugins['nocache'][$tag][$plugin_type]['function'] =
							$callback;
					} else {
						$this->parent_compiler->template->compiled->required_plugins['compiled'][$tag][$plugin_type]['file'] =
							$script;
						$this->parent_compiler->template->compiled->required_plugins['compiled'][$tag][$plugin_type]['function'] =
							$callback;
					}
					require_once $script;
				} else {
					$this->trigger_template_error("Default plugin handler: Returned script file \"{$script}\" for \"{$tag}\" not found");
				}
			}
			if (is_callable($callback)) {
				$this->default_handler_plugins[$plugin_type][$tag] = array($callback, true, array());

				return true;
			} else {
				$this->trigger_template_error("Default plugin handler: Returned callback for \"{$tag}\" not callable");
			}
		}

		return false;
	}

	/**
	 * Append code segments and remove unneeded ?> <?php transitions
	 *
	 * @param string $left
	 * @param string $right
	 *
	 * @return string
	 */
	public function appendCode($left, $right) {
		if (preg_match('/\s*\?>\s*$/', $left) && preg_match('/^\s*<\?php\s+/', $right)) {
			$left = preg_replace('/\s*\?>\s*$/', "\n", $left);
			$left .= preg_replace('/^\s*<\?php\s+/', '', $right);
		} else {
			$left .= $right;
		}
		return $left;
	}

	/**
	 * Inject inline code for nocache template sections
	 * This method gets the content of each template element from the parser.
	 * If the content is compiled code and it should be not cached the code is injected
	 * into the rendered output.
	 *
	 * @param  string  $content content of template element
	 * @param  boolean $is_code true if content is compiled code
	 *
	 * @return string  content
	 */
	public function processNocacheCode($content, $is_code) {
		// If the template is not evaluated and we have a nocache section and or a nocache tag
		if ($is_code && !empty($content)) {
			// generate replacement code
			if ((!($this->template->source->handler->recompiled) || $this->forceNocache) && $this->template->caching &&
				!$this->suppressNocacheProcessing && ($this->nocache || $this->tag_nocache)
			) {
				$this->template->compiled->has_nocache_code = true;
				$_output = addcslashes($content, '\'\\');
				$_output = str_replace("^#^", "'", $_output);
				$_output = "<?php echo '/*%%SmartyNocache:{$this->nocache_hash}%%*/" . $_output .
					"/*/%%SmartyNocache:{$this->nocache_hash}%%*/';?>\n";
				// make sure we include modifier plugins for nocache code
				foreach ($this->modifier_plugins as $plugin_name => $dummy) {
					if (isset($this->parent_compiler->template->compiled->required_plugins['compiled'][$plugin_name]['modifier'])) {
						$this->parent_compiler->template->compiled->required_plugins['nocache'][$plugin_name]['modifier'] =
						$this->parent_compiler->template->compiled->required_plugins['compiled'][$plugin_name]['modifier'];
					}
				}
			} else {
				$_output = $content;
			}
		} else {
			$_output = $content;
		}
		$this->modifier_plugins = array();
		$this->suppressNocacheProcessing = false;
		$this->tag_nocache = false;

		return $_output;
	}

	/**
	 * Get Id
	 *
	 * @param string $input
	 *
	 * @return bool|string
	 */
	public function getId($input) {
		if (preg_match('~^([\'"]*)([0-9]*[a-zA-Z_]\w*)\1$~', $input, $match)) {
			return $match[2];
		}
		return false;
	}

	/**
	 * Get variable name from string
	 *
	 * @param string $input
	 *
	 * @return bool|string
	 */
	public function getVariableName($input) {
		if (preg_match('~^[$]_smarty_tpl->tpl_vars\[[\'"]*([0-9]*[a-zA-Z_]\w*)[\'"]*\]->value$~', $input, $match)) {
			return $match[1];
		}
		return false;
	}

	/**
	 * Set nocache flag in variable or create new variable
	 *
	 * @param string $varName
	 */
	public function setNocacheInVariable($varName) {
		// create nocache var to make it know for further compiling
		if ($_var = $this->getId($varName)) {
			if (isset($this->template->tpl_vars[$_var])) {
				$this->template->tpl_vars[$_var] = clone $this->template->tpl_vars[$_var];
				$this->template->tpl_vars[$_var]->nocache = true;
			} else {
				$this->template->tpl_vars[$_var] = new Smarty_Variable(null, true);
			}
		}
	}

	/**
	 * @param array $_attr tag attributes
	 * @param array $validScopes
	 *
	 * @return int|string
	 * @throws \SmartyCompilerException
	 */
	public function convertScope($_attr, $validScopes) {
		$_scope = 0;
		if (isset($_attr['scope'])) {
			$_scopeName = trim($_attr['scope'], "'\"");
			if (is_numeric($_scopeName) && in_array($_scopeName, $validScopes)) {
				$_scope = $_scopeName;
			} elseif (is_string($_scopeName)) {
				$_scopeName = trim($_scopeName, "'\"");
				$_scope = isset($validScopes[$_scopeName]) ? $validScopes[$_scopeName] : false;
			} else {
				$_scope = false;
			}
			if ($_scope === false) {
				$err = var_export($_scopeName, true);
				$this->trigger_template_error("illegal value '{$err}' for \"scope\" attribute", null, true);
			}
		}
		return $_scope;
	}

	/**
	 * Generate nocache code string
	 *
	 * @param string $code PHP code
	 *
	 * @return string
	 */
	public function makeNocacheCode($code) {
		return "echo '/*%%SmartyNocache:{$this->nocache_hash}%%*/<?php " .
		str_replace("^#^", "'", addcslashes($code, '\'\\')) .
			"?>/*/%%SmartyNocache:{$this->nocache_hash}%%*/';\n";
	}

	/**
	 * display compiler error messages without dying
	 * If parameter $args is empty it is a parser detected syntax error.
	 * In this case the parser is called to obtain information about expected tokens.
	 * If parameter $args contains a string this is used as error message
	 *
	 * @param  string   $args    individual error message or null
	 * @param  string   $line    line-number
	 * @param null|bool $tagline if true the line number of last tag
	 *
	 * @throws \SmartyCompilerException when an unexpected token is found
	 */
	public function trigger_template_error($args = null, $line = null, $tagline = null) {
		$lex = $this->parser->lex;
		if ($tagline === true) {
			// get line number of Tag
			$line = $lex->taglineno;
		} elseif (!isset($line)) {
			// get template source line which has error
			$line = $lex->line;
		} else {
			$line = (int) $line;
		}

		if (in_array($this->template->source->type, array('eval', 'string'))) {
			$templateName = $this->template->source->type . ':' . trim(preg_replace('![\t\r\n]+!', ' ',
				strlen($lex->data) > 40 ?
				substr($lex->data, 0, 40) .
				'...' : $lex->data));
		} else {
			$templateName = $this->template->source->type . ':' . $this->template->source->filepath;
		}

		//        $line += $this->trace_line_offset;
		$match = preg_split("/\n/", $lex->data);
		$error_text =
		'Syntax error in template "' . (empty($this->trace_filepath) ? $templateName : $this->trace_filepath) .
		'"  on line ' . ($line + $this->trace_line_offset) . ' "' .
		trim(preg_replace('![\t\r\n]+!', ' ', $match[$line - 1])) . '" ';
		if (isset($args)) {
			// individual error message
			$error_text .= $args;
		} else {
			$expect = array();
			// expected token from parser
			$error_text .= ' - Unexpected "' . $lex->value . '"';
			if (count($this->parser->yy_get_expected_tokens($this->parser->yymajor)) <= 4) {
				foreach ($this->parser->yy_get_expected_tokens($this->parser->yymajor) as $token) {
					$exp_token = $this->parser->yyTokenName[$token];
					if (isset($lex->smarty_token_names[$exp_token])) {
						// token type from lexer
						$expect[] = '"' . $lex->smarty_token_names[$exp_token] . '"';
					} else {
						// otherwise internal token name
						$expect[] = $this->parser->yyTokenName[$token];
					}
				}
				$error_text .= ', expected one of: ' . implode(' , ', $expect);
			}
		}
		$e = new SmartyCompilerException($error_text);
		$e->line = $line;
		$e->source = trim(preg_replace('![\t\r\n]+!', ' ', $match[$line - 1]));
		$e->desc = $args;
		$e->template = $this->template->source->filepath;
		throw $e;
	}

	/**
	 * Return var_export() value with all white spaces removed
	 *
	 * @param  mixed $value
	 *
	 * @return string
	 */
	public function getVarExport($value) {
		return preg_replace('/\s/', '', var_export($value, true));
	}

	/**
	 * Check if $value contains variable elements
	 *
	 * @param mixed $value
	 *
	 * @return bool|int
	 */
	public function isVariable($value) {
		if (is_string($value)) {
			return preg_match('/[$(]/', $value);
		}
		if (is_bool($value) || is_numeric($value)) {
			return false;
		}
		if (is_array($value)) {
			foreach ($value as $k => $v) {
				if ($this->isVariable($k) || $this->isVariable($v)) {
					return true;
				}
			}
			return false;
		}
		return false;
	}

	/**
	 * Get new prefix variable name
	 *
	 * @return string
	 */
	public function getNewPrefixVariable() {
		self::$prefixVariableNumber++;
		return $this->getPrefixVariable();
	}

	/**
	 * Get current prefix variable name
	 *
	 * @return string
	 */
	public function getPrefixVariable() {
		return '$_prefixVariable' . self::$prefixVariableNumber;
	}

	/**
	 * append  code to prefix buffer
	 *
	 * @param string $code
	 */
	public function appendPrefixCode($code) {
		$this->prefix_code[] = $code;
	}

	/**
	 * get prefix code string
	 *
	 * @return string
	 */
	public function getPrefixCode() {
		$code = '';
		$prefixArray = array_merge($this->prefix_code, array_pop($this->prefixCodeStack));
		$this->prefixCodeStack[] = array();
		foreach ($prefixArray as $c) {
			$code = $this->appendCode($code, $c);
		}
		$this->prefix_code = array();
		return $code;
	}

}
